Methods of using phenolic fatty acid compound on a non-phenolic polymer

ABSTRACT

This invention relates to a process for making phenolic fatty acid compounds having a reduced phenolic ester content. The invention also relates to method for chemically bonding a phenolic resin with a non-phenolic polymer (e.g., a synthetic fabric). The method comprises contacting a phenolic fatty acid compound with a non-phenolic polymer to introduce a hydroxy phenyl functional group into the non-phenolic polymer; and reacting the hydroxy phenyl functional group contained in the non-phenolic polymer with a phenolic resin or a phenolic crosslinker composition capable of forming a phenolic resin, to chemically bond the phenolic resin with the non-phenolic polymer. The invention is particularly useful for making a synthetic fabric-reinforced article, such as synthetic fabric-reinforced rubber article, circuit board substrate, or fiberglass.

This application claims priority to U.S. Provisional Application No.61/953,455, filed on Mar. 14, 2014, which is herein incorporated byreference in its entirety.

FIELD OF THE INVENTION

This invention generally relates to a process for making phenolic fattyacid compounds and using the resulting phenolic fatty acid compounds tochemically bond a phenolic resin with a non-phenolic polymer, e.g., afabric material. This invention is particularly useful for making asynthetic fabric-reinforced article.

BACKGROUND

Fabric-reinforced polymer materials are a category of compositematerials that use fabric materials to mechanically enhance the strengthand elasticity of the polymer materials. For example, rubber articlessuch as tires, hoses, and belts are composite materials of variousnatural and synthetic rubber compositions reinforced with differentreinforcing materials such as reinforced fibers made from syntheticfabric materials.

When forming the composite materials, it is desirable to achieve goodadhesion between the reinforcing fabric phase and the polymer matrixphase (i.e., the polymer material without fabric reinforcement) tomaintain the integrity of the composite material. However syntheticfabrics have difficulty of adhering to the polymer matrix because oftheir generally smooth polymer surfaces and low surface activity,typically because of their lower polarity and reactivity of the polymermolecules in the fabric material.

To promote the adhesion between the reinforcing fabric phase and thepolymer matrix phase, much of the current technology employs adhesivesand related applying processes. For example, two adhesive systems arewidely used to promote the adhesion between the reinforcing fabric fiberand the rubber compositions in tire industry: theresorcinol-formaldehyde-latex (RFL) coating method where an RFL adhesiveis applied to the fabric cord, and the hexamethylenetetramine-resorcinolor hexamethoxymethylmelamine-resorcinol adhesion promoting methods inwhich an adhesion promotion system is incorporated into the rubbercomposition.

However, none of the existing technology sufficiently establishes achemical bonding between the fabric phase and the phenolic adhesive topromote the strong adhesion between the fabric phase and the polymermatrix phase. Therefore, there remains a need in the art to develop animproved method to achieve a better adhesion between the reinforcingfabric phase and the polymer matrix phase. A particular need exists inthe rubber industry to provide an improved bonding between thereinforced fabric material and the rubber composition. This inventionanswers that need.

SUMMARY OF THE INVENTION

One aspect of the invention relates to a process for making a phenolicfatty acid compound having a reduced phenolic ester content. The methodcomprises providing a fatty acid composition comprising at least oneunsaturated fatty acid, and reacting a phenolic compound with the fattyacid composition in the presence of an acidic catalyst at a temperatureranging from about 90° C. to about 120° C. to form the phenolic fattyacid compound. The method produces a phenolic fatty acid compound withless than 5 wt % phenolic ester.

Another aspect of the invention relates to a method for chemicallybonding a phenolic resin with a non-phenolic polymer. The methodcomprises contacting a phenolic fatty acid compound with a non-phenolicpolymer having a functional group reactive to a carboxylic acid group ofa fatty acid, to react the carboxylic acid-reactive functional group ofthe non-phenolic polymer with the carboxylic acid group of the phenolicfatty acid compound, thereby attaching a hydroxy phenyl functional groupto the non-phenolic polymer. The method further comprises reacting thehydroxy phenyl functional group of the non-phenolic polymer with aphenolic resin or a phenolic crosslinker composition capable of forminga phenolic resin, to chemically bond the phenolic resin with thenon-phenolic polymer.

Another aspect of the invention relates to a method for chemicallybonding a phenolic resin with a synthetic fabric material. The methodcomprises contacting a phenolic fatty acid compound with a syntheticfabric material to introduce a hydroxy phenyl functional group into thesynthetic fabric material. The method further comprises reacting thehydroxy phenyl functional group contained in the synthetic fabricmaterial with a phenolic resin or a phenolic crosslinker compositioncapable of forming a phenolic resin, to chemically bond the phenolicresin with the synthetic fabric material.

Another aspect of the invention relates to a synthetic-fabric reinforcedrubber composition. The composition comprises a rubber composition and asynthetic fabric phase. The synthetic fabric phase has been (a) modifiedby a phenolic fatty acid compound to contain a hydroxy phenyl functionalgroup, and (b) coated with a phenolic resin, wherein the syntheticfabric phase and the coated phenolic resin are chemically bonded throughthe hydroxy phenyl functional group. The synthetic fabric phase is usedas reinforced materials for the rubber composition.

Another aspect of the invention relates to a synthetic-fabric reinforcedarticle. The article comprises an article containing a phenolic resin,and a synthetic fabric phase. The synthetic fabric phase is modified bya phenolic fatty acid compound to contain a hydroxy phenyl functionalgroup. The synthetic fabric phase and the article are chemically bondedthrough the hydroxy phenyl functional group. The article can be a rubbercomposition, a circuit board substrate, or a fiberglass.

Additional aspects, advantages and features of the invention are setforth in this specification, and in part will become apparent to thoseskilled in the art on examination of the following, or may be learned bypractice of the invention. The inventions disclosed in this applicationare not limited to any particular set of or combination of aspects,advantages and features. It is contemplated that various combinations ofthe stated aspects, advantages and features make up the inventionsdisclosed in this application.

DETAILED DESCRIPTION OF THE INVENTION

This invention relates to a process for making phenolic fatty acidcompounds and using the resulting phenolic fatty acid compounds tochemically bond a phenolic resin with a non-phenolic polymer, e.g., afabric material. The non-phenolic polymer (e.g., a synthetic fabric)typically does not react, or reacts only minimally, with the phenolicresin, without the presence of the phenolic fatty acid compound. Themethod takes advantage of the bi-functionality of the phenolic fattyacid compound, i.e., the carboxylic acid functionality and the hydroxyphenyl functionality, to chemically bond the non-phenolic polymer phaseand the phenolic resin phase. This invention is particularly useful formaking a synthetic fabric-reinforced article, such as syntheticfabric-reinforced rubber article, circuit board substrate, orfiberglass.

Process of Making a Phenolic Fatty Acid Compound

One aspect of the invention relates to a process for making a phenolicfatty acid compound having a reduced phenolic ester content. The methodcomprises providing a fatty acid composition comprising at least oneunsaturated fatty acid, and reacting a phenolic compound with the fattyacid composition in the presence of an acidic catalyst at a temperatureranging from about 90° C. to about 120° C. to form the phenolic fattyacid compound. The method produces a phenolic fatty acid compound withless than 5 wt % phenolic ester.

The phenolic compound may be a monohydric, dihydric, or polyhydricphenol. Suitable monohydric, dihydric, or polyhydric phenols include,but are not limited to, phenol; dihydricphenols such as resorcinol,catechol, and hydroquinone; dihydroxybiphenol; alkylidenebisphenols suchas 4,4′-methylenediphenol (bisphenol F), and 4,4′-isopropylidenediphenol(bisphenol A); trihydroxybiphenol; and thiobisphenols. The benzene ringof the monohydric, dihydric, or polyhydric phenols can be substituted inthe ortho, meta, and/or para positions by one or more linear, branched,or cyclic C₁-C₃₀ alkyl, or halogen (F, Cl, or Br). For example, thebenzene ring can be substituted by C₁-C₁₆ alkyl, C₁-C₆ alkyl, or C₁-C₄alkyl. Suitable substituents on the benzene ring also include C₁-C₃₀aralkyl, C₁-C₃₀ alkanoyl, and C₁-C₃₀ aroyl. Exemplary phenolic compoundsinclude phenol or resorcinol; or phenol or resorcinol substituted withone or more methyl groups, such as cresol, xylenol, or methylresorcinol.

The fatty acid composition can come from any natural oils or fats, orprocessed source of fatty acids that provide one or more unsaturatedfatty acids. Suitable oils include, but are not limited to, a variety ofvegetable oils such as soybean oil, peanut oil, walnut oil, palm oil,palm kernel oil, wheat germ oil sesame oil, sunflower oil, saffloweroil, rapeseed oil, linseed oil, flax seed oil, colza oil, coconut oil,corn oil, cottonseed oil, olive oil, castor oil, false flax oil, hempoil, mustard oil, radish oil, ramtil oil, rice bran oil, salicornia oil,tigernut oil, tung oil, and mixtures thereof. Suitable fats include, butare not limited to, beef or mutton fat such as beef tallow or muttontallow; pork fat such as pork lard; poultry fat such as turkey and/orchicken fat, or duck fat; and fish fat/oil. Typical fatty acidcompositions used include commercially available oils or fats thatcontain a large amount of mixed unsaturated fatty acids, derived from,for instance, cotton, soy, linseed oil, or tall oil. The fatty acidcomposition may comprise one or more fatty acids listed in Table 1.Commercially available unsaturated fatty acids such as undecylenic acid,oleic acid, linoleic acid, linolenic acid, palmitoleic acid, and erucicacid, as well as isomeric modifications of these acids can also be used.An exemplary fatty acid composition comprises oleic acid, linoleic acid,linolenic acid, or mixtures thereof.

TABLE 1 Suitable unsaturated fatty acids for making a phenolic fattyacid compound Common name Chemical structure Property Myristoleic CH

(CH₂)

CH═CH(CH₂)₇COOH Unsaturated fatty acid acid with C

 and one double bond Palmitoleic CH

(CH₂)₅CH═CH(CH₂)₇COOH Unsaturated fatty acid acid with C₁₅ and onedouble bond Sapienic CH

(CH₂)₈CH═CH(CH₂)₄COOH Unsaturated fatty acid acid with C₁₅ and onedouble bond Oleic CH₂(CH₂)₇CH═CH(CH₂)₇COOH Unsaturated fatty acid acidwith C

 and one double bond Elaidic CH

(CH₂)₇CH═CH(CH₂)₇COOH Unsaturated fatty acid acid with C

 and one double bond Vaccenic CH₃(CH₂)₅CH═CH(CH₂)₉COOH Unsaturated fattyacid acid with C

 and one double bond Elaidic CH₃(CH₂)₇CH═CH(CH₂)₇COOH Unsaturated fattyacid acid with C

 and one double bond Vaccenic CH₂(CH₂)₃CH═CH(CH₂)₉COOH Unsaturated fattyacid acid with C

 and one double bond Linoleic CH₃(CH₂)₄CH═CHCH₂CH═CH(CH₂)₇COOHPolyunsaturated fatty acid acid with C

 and two double bonds Linoelaidic CH₂(CH₂)₄CH═CHCH₂CH═CH(CH₂)₇COOHPolyunsaturated fatty acid acid with C

 and two double bonds α-Linolenic CH₃CH₂CH═CHCH₂CH═CHCH₂CH═CH(CH₂)₇COOHPolyunsaturated fatty acid acid with C

 and three double bonds Arachidonic CH

(CH₂)₄CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CH(CH₂)₂COOH Polyunsaturated fatty acidacid with C₂₀ and four double bonds Eicosa-CH₂CH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CHCH₂CH═CH(CH₂)₃COOH Polyunsaturatedfatty pentaenoic acid with C₂₀ and acid five double bonds ErucicCH₂(CH₂)₇CH═CH(CH₂)₁₁COOH Unsaturated fatty acid acid with C₂₂ and onedouble bond Docosa- CH₂CH₂CH═CHCH₂CH═CHCH₃CH═CHCH₂CH═CHCH

CH═CHCH

CH═CH(CH

)

COOH Polyunsaturated fatty hexaenoic acid with C₂₂ and acid six doublebonds

indicates data missing or illegible when filed

The reaction of the phenolic compound with the fatty acid compositioninvolves alkylation of the phenolic compound with the unsaturated fattyacid, in which the reaction occurs at the double bond of the fatty acidand adds the phenol benzene ring and a hydrogen atom to each unsaturatedcarbon atom of the double bond in the fatty acid. For example, a phenolstearic acid compound can be prepared from the reaction of oleic acidand phenol, with the primary reaction product being[9,10]-(hydroxyphenol)-octadecanoic acid), as shown in Scheme 1.

When a mixture of unsaturated fatty acids are present in the fatty acidcomposition, each unsaturated fatty acid can react with the phenoliccompound, thereby forming a mixture of phenolic fatty acid compoundswhere the phenol benzene rings are alkylated with various fatty acids.When the fatty acid composition contains one or more polyunsaturatedfatty acids, the reaction of the phenol benzene ring of the phenoliccompound with the fatty acid may occur at one or more double bondswithin the polyunsaturated fatty acid, i.e., the resulting phenolicfatty acid product may contain a mixture of a completely saturatedaliphatic chain, and a partially saturated aliphatic chain. For example,when phenol reacts with linolenic acid, which contains two double bonds,the resulting phenolic fatty acid product may be phenol stearic acid(two double bonds are completely saturated by addition of the phenolbenzene rings), phenolic oleic acid (only one double bond is saturatedby addition of the phenol benzene ring, and another double bond is leftunsaturated), or a mixture thereof. Exemplary reactions also includereacting phenol with palmitoleic acid or linolenic acid to form phenolpalmitic acid or phenol behenic acid, respectively.

The reaction of the phenolic compound with the fatty acid compositioncan result a byproduct of phenolic ester, formed by the reaction of thehydroxyl group of the phenolic compound with the carboxyl group of thefatty acids. The resulting undesirable phenolic ester byproducts mixwith the phenolic fatty acid product and cause coloration of thephenolic fatty acid product, which impairs the subsequent usage of thephenolic fatty acid product. To improve the effectiveness of alkylationof the phenolic compound with the unsaturated fatty acid, reduce theesterification byproduct, and decolor the phenolic fatty acid product,the reaction is carried out in the presence of an acidic catalyst at atemperature ranging from about 90° C. to about 120° C. This low reactiontemperature can significantly reduce the formation of phenolic esterbyproducts.

Suitable acidic catalysts include, but are not limited to, sulfuricacid, ethanesulfonic acid, benzenesulfonic acid, benzenedisulfonic acid,chlorobenzenesulfonic acid, 3,4-dichlorobenzene sulfonic acid,cresolsulfonic acids, phenol sulfonic acids, toluenesulfonic acids,xylenesulfonic acids, octylphenolsulfonic acid, naphthalenesulfonicacid, 1-naphthol-4-sulfonic acid, dodecylsulfonic acid, and oxalic acid.An exemplary catalyst is sulfuric acid or a sulfonic acid, such asp-toluenesulfonic acid (PTSA). A catalyst media can be used forsuspending the homogeneous acidic catalyst. For example, surface-activeclay minerals such as montmorillonite, hectorite, halloysite,attapulgite, and sepiolite can be used. The amount of the acidiccatalyst used in the reaction mixture may range from about 1 wt % toabout 20 wt %, or from about 2 wt % to about 10 wt % of the totalreactants. When using the acidic catalysts, the amounts of water ormoisture content may be minimized to avoid poisoning the catalyst. Theamount of water or moisture content may be present to up to 10 wt %, orup to 5 wt %.

The weight ratio of the phenolic compound to the unsaturated fatty acidcomposition typically ranges from about 2:1 to about 5:1, but can behigher.

In carrying out the above reaction between the phenolic compound and theunsaturated fatty acid, the temperature can range from about 90° C. toabout 120° C., from about 90° C. to about 110° C., from about 90° C. toabout 105° C., or from about 90° C. to about 100° C. Significantly abovethis temperature range results in higher ester formation. The reactioncan last for from about 1 hour to about 10 hours, or from about 3 hoursto about 8 hours.

After the reaction is complete, the acidic catalyst can be neutralizedwith an aqueous base, such as aqueous sodium hydroxide. The remainingphenolic compound, if any, can be removed by distillation. If a catalystmedia is used for suspending the acidic catalyst, the catalyst media isremoved prior to distillation. The distillation can be a vacuumdistillation, and can be carried out at a temperature ranging from about120° C. to about 140° C., or about 130° C. These steps further reducethe ester content.

Using the above reaction conditions, the content of the phenolic esterin the resulting phenolic fatty acid compound can be reduced to lessthan 5 wt %, less than 3 wt % or less than 1 wt %.

Use of Phenolic Fatty Acid Compounds

One aspect of the invention relates to a method for chemically bonding aphenolic resin with a non-phenolic polymer. The method comprisescontacting a phenolic fatty acid compound with a non-phenolic polymerhaving a functional group reactive to a carboxylic acid group of a fattyacid, to react the carboxylic acid-reactive functional group of thenon-phenolic polymer with the carboxylic acid group of the phenolicfatty acid compound, thereby attaching a hydroxy phenyl functional groupto the non-phenolic polymer. The method further comprises reacting thehydroxy phenyl functional group of the non-phenolic polymer with aphenolic resin or a phenolic crosslinker composition capable of forminga phenolic resin, to chemically bond the phenolic resin with thenon-phenolic polymer.

The non-phenolic polymer does not react, or only reacts minimally, withthe phenolic resin, without the presence of the phenolic fatty acidcompound. The method takes advantage of the bi-functionality of thephenolic fatty acid compound, i.e., the carboxylic acid functionalityand the hydroxy phenyl functionality, to chemically bond thenon-phenolic polymer phase and the phenolic resin phase.

One aspect of the reaction involves the carboxylic acid group of thephenolic fatty acid compound reacting with a carboxylic acid-reactivefunctional group within the non-phenolic polymer, e.g, —OR, —COOR,CH₂═CHCOOR, —NH, or —CONH, to introduce the hydroxy phenyl functionalityfrom the phenolic fatty acid compound into the non-phenolic polymer.This reaction typically occurs in the presence of a metal-based catalystor an acidic catalyst.

Suitable metal-based catalysts include, but are not limited to, anantimony-based catalyst such as antimony trioxide, antimony glucoxide,antimony butoxide, acetyl antimony dibutoxide, antimony triacetate; atin-based catalyst such as dibutyltin oxide (DBTO), dioctyltin oxide(DOTO), mono butylchlorotin dihydroxide, mono butyloxide (MBTO),dibutyltin diacetate (DBTA), dibutyltin maleate dibutyltin dilaurate(DBTL), dioctyltin dilaurate (DOTL), butyltin tris(2-ethylhexanoate),and lauryl stannoxane; a titanium-based catalyst such as alkyl titanate(e.g., titanium tetraisobutoxide, tetraisopropyl titanate,tetra-n-butyl-titanate, tetramethyl titanate, acetyl triisopropyltitanate, tetraisobutyl titanate), titanium alkoxide, titaniumtetrachloride, titanyl oxalate and orthotitanic acid; and a co-catalystof phosphorus and any metal element of beryllium, magnesium, calcium,strontium, barium, boron, aluminum, gallium, tin, manganese, cobalt,zinc, germanium, and antimony; and combinations thereof.

Suitable acidic catalysts include, but are not limited to, a lewis acid;a strong acid catalyst such as one or more sulfonic acids or otherstrong acids (an acid with a pKa about 3 or less); a triflic acid; atriflate salt of a metal of Group IIA, IIB, IIIA, IIIB, or VIIIA of thePeriodic Table of Elements, e.g., the Group IIA metal triflate catalystssuch as magnesium triflate, the Group IIB metal triflate catalysts suchas zinc and cadmium triflate, the Group IIIA metal triflate catalystssuch as lanthanum triflate, the Group IIIB metal triflate catalysts suchas aluminum triflate, and the Group VIIIA metal triflate catalysts suchas cobalt triflate; a mixture of the triflate salts; and combinationsthereof.

The amount of catalysts can range from about 1 ppm to about 10,000 ppm,or from about 10 ppm to about 1,000 ppm, based on the total weight ofthe reaction mixture. For example, the amount of each metal triflatecatalyst can range from about 10 to about 1,000 ppm, or from about 10 toabout 200 ppm, based on the total weight of the reaction mixture. Ametal triflate catalyst can be used in the form of a solution or in anorganic solvent. Exemplary organic solvents include water; alcohols suchas n-butanol, ethanol, propanol; aromatic hydrocarbon solvents;cycloaliphatic polar solvents such as cycloaliphatic ketones (e.g.cyclohexanone); polar aliphatic solvents such as alkoxyalkanols,2-methoxyethanol; non-hydroxyl functional solvents; and mixturesthereof.

The other aspect of the invention involves the hydroxy phenylfunctionality of the phenolic fatty acid compound (i.e., the functionalgroup that is being introduced into the non-phenolic polymer) chemicallyreacting with hydroxymethyl or other methylene donors in the phenolicresin. This reaction results in a covalent bond between the two species.

The reaction typically occurs in the presence of a basic catalyst.Suitable basic catalysts include, but are not limited to, ammoniumhydroxide, tertiary amines, alkali and alkaline earth metal oxides andhydroxides, and combinations thereof.

A phenolic fatty acid compound refers to a phenolic compound with thephenol benzene ring alkylated by the aliphatic chains of a fatty acid.The reaction mechanism of the phenolic fatty acid compound formation andsuitable reagents for this alkylation reaction, i.e., suitable phenoliccompounds and unsaturated fatty acids, have been discussed in the aboveembodiments. Any phenolic fatty acid compound resulting from thealkylation of the phenolic compound with the unsaturated fatty aciddiscussed in the above embodiments can be used in this method.Commercially available phenolic fatty acid compound can also be used.Exemplary phenolic fatty acid compounds include hydroxyphenyl stearicacid (e.g., [9,10]-(p-hydroxyphenyl)-octadecanoic acid), hydroxyphenyloleic acid, hydroxyphenyl linoleic acid, hydroxyphenyl palmitic acid,hydroxyphenyl behenic acid, and combinations thereof. The phenolic fattyacid compound can be used in an amount ranging from about 0.1 wt % toabout 50 wt %, for instance, from about 0.1 wt % to about 20 wt %, fromabout 1 wt % to about 15 wt %, from about 2 wt % to about 10 wt %, fromabout 5 wt % to about 50 wt %, or from about 5 wt % to about 20 wt % ofthe non-phenolic polymer. In one embodiment, the phenolic fatty acidcompound is hydroxyphenyl stearic acid, and is used in an amount rangingfrom about 0.1 wt % to about 20 wt %, for instance, from about 1 wt % toabout 15 wt %, or from about 2 wt % to about 10 wt % of the non-phenolicpolymer.

Non Phenolic Polymers

Suitable non-phenolic polymers include, but are not limited to, apolyester, a polyether, a polyacetate, an acrylic compound, a polyamide,a polyamine, a polysulfone, an epoxy, and combinations thereof. Thenon-phenolic polymer suitable for use herein contain at least onecarboxylic acid-reactive functional group, e.g, an —OR, —COOR,CH₂═CHCOOR, —NH, or —CONH, to react with carboxylic acid group of thephenolic fatty acid compound.

The non-phenolic polymers can be prepared by methods known to oneskilled in the art. For example, a polyester can be prepared from a dioland a diacid, such that hydroxyl, amine, or glycidyl groups areavailable to react with the carboxylic acid of the phenolic fatty acidcompound. Suitable polyesters include, but are not limited to,polyglycolic acid (PGA) polylactic acid (PLA), polycaprolactone (PCL),polyhydroxyalkanoate (PHA), polyhydroxybutyrate (PHB), polyethyleneadipate (PEA), polybutylene succinate (PBS),poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), polyethyleneterephthalate (PET) (e.g., Mylar® from DuPont), polybutyleneterephthalate (PBT), polytrimethylene terephthalate (PTT), polyethylenenaphthalate (PEN), and vectran.

Suitable polyethers include, but are not limited to, polyoxymethylene(POM), polyacetal or polyformaldehyde (e.g., Delrin® from DuPont);polyethylene glycol (PEG), or polyethylene oxide (PEO) (e.g., CARBOWAX™from Dow); polypropylene glycol (PPG) or polypropylene oxide (PPO);polytetramethylene glycol (PTMG) or polytetrahydrofuran (PTHF) (e.g.,TERATHANE® from INVISTA); polytetramethylene ether glycol (PTMEG) (e.g.,PolyTHF® from BASF); phenyl ether (PPE); and poly(p-phenylene oxide).

Polyacetate typically refers to polyvinyl acetate (PVA). PVA can beprepared by polymerization of vinyl acetate monomer (free radical vinylpolymerization of the monomer vinyl acetate). Suitable polyacetate canalso include ethylene vinyl acetate (EVA), and polyvinyl acetatephthalate (PVAP).

Polyacrylic may be prepared from an ethylenically unsaturated monomercomponent having non-functional ethylenically unsaturated monomers suchas butyl acrylate, methyl methacrylate, styrene, benzyl methacrylate,and mixtures thereof; and optionally with lesser amounts of functionalmonomers such as hydroxy propyl methacrylate, hydroxy ethyl acrylate,glycidyl methacrylate, acrylic acid, methacrylic acid, acetoacetoxyethyl methacrylate, phosphate esters monomethacrylate and mixturesthereof. In some embodiments, the monomer providing hydroxylfunctionality is added at a level up to about 30 wt % of theethylenically unsaturated monomer component mixture, the monomerproviding acid functionality is added at a level up to about 30 wt % ofthe ethylenically unsaturated monomer component mixture. In someembodiments, acetoacetoxy ethyl methacrylate is added at a level up toabout 30 wt % of the ethylenically unsaturated monomer componentmixture. Phosphate esters of monomethacrylates (such as Sipomer Pam-100,Pam-200 and Pam-400) can be added at a level up to about 20 wt % of theethylenically unsaturated monomer component mixture. In someembodiments, about 10 to about 50 wt % of the ethylenically unsaturatedmonomer component mixture is a monomer having an acid functionality. Insome embodiments, the monomer providing an acid functionality ismethacrylic acid. In certain embodiments, glycidyl methacrylate is usedat levels of about 10 to about 20 wt % of the ethylenically unsaturatedmonomer component mixture, and the phenolic fatty acid compound, isadducted with the acrylic polymer after it is formed.

The initiator used to polymerize the ethylenically unsaturated monomersmay include azo compounds such as 2,2′-azo-bis(isobutyronitrile),2,2′-azo-bis(2,4-dimethylvaleronitrile), and1-t-butyl-azocyanocyclohexane); hydroperoxides such as t-butylhydroperoxide and cumene hydroperoxide; peroxides such as benzoylperoxide, caprylyl peroxide, di-t-butyl peroxide, ethyl3,3′-di(t-butylperoxy) butyrate, ethyl 3,3′-di(t-amylperoxy) butyrate,t-amylperoxy-2-ethyl hexanoate,1,1,3,3-tetramethylbutyl-peroxy-2-ethylhexanoate, and t-butylperoxypivilate; peresters such as t-butyl peracetate, t-butyl perphthalate,and t-butyl perbenzoate; percarbonates, such asdi(1-cyano-1-methylethyl)peroxy dicarbonate, perphosphates, and t-butylperoctoate; and mixtures thereof. In some embodiments, the initiator ispresent in an amount from about 0.1 to about 15 wt %, or from about 1 toabout 5 wt % of the monomer mixture. In some embodiments, the initiatoris added over about 2 hours, simultaneously with the monomers as a feedto a solvent mixture, held at a suitable temperature relative to thehalf-life of the initiator.

Suitable polyamides include, but are not limited to, aliphaticpolyamides, such as PA 6 and PA 66 (e.g., Nylon from DuPont; TECHNYL®from Rhodia; Rilsan® and Rilsamid® from Arkema); polyphthalamides (PPA)(e.g, Trogamid® from Evonik Industries; Amodel® from Solvay); andAramides (such as Kevlar® and Nomex® from DuPont; Teijinconex, Twaronand Technora from Teijin; Kermel from Kermel; and Spectra® fromHoneywell.); as well as mixed aliphatic polyamides/aromatic polyamides.For instance, polyamides can be prepared from reacting diamines, such asethylene diamine, hexamethylene diamine, piperazine, or mixturesthereof, with diacids, such as isophthalic acid, adipic acid, dimerfatty acids, cyclohexanedioic acid, naphthalenedioic acid, terephthalicacid, or mixtures thereof. Triacids, triols, or any other glycols may beincluded to provide branching to the polymer (the resulting polymer canbe considered as a polyester-amide); and the phenolic fatty acidcompound may react with either the amine functionality or the hydroxylfunctionality.

Suitable polyamines include, but are not limited to, polyethylene amine,piperazine, cyclen, and cyclam. Polyamine can also be prepared basedfrom ethylene diamine, 1,3-diaminopropane, and hexamethylenediamine.

A typical polysulfone is produced by the reaction of a diphenol andbis(4-chlorophenyl)sulfone, forming a polyether by elimination of sodiumchloride. The diphenol is typically bisphenol-A or 1,4-dihydroxybenzene.Suitable polysulfones include, but are not limited to, polysulfones(e.g., Udel®), polyarylsulfones (e.g., Astrel), polyether sulfones(e.g., Ultrason®), or polyarylethesulfones (e.g., VICTREX®).

The non-phenolic polymer can be a synthetic fabric material forutilization as a reinforcing material. Suitable synthetic fabricmaterials include, but are not limited to, nylon, rayon, polyester,aramid, polysulfone, or other organic and inorganic compositions, asdiscussed and exemplified in the above embodiments. These syntheticfabric materials may be in the form of, for instance, filaments, fibers,cords, or fabric sheets.

Phenolic Resins

A phenolic resin or a phenolic crosslinker composition capable offorming a phenolic resin is used in the method. Any phenolic compoundknown in the art suitable for the condensation reaction with one or morealdehydes may be used to prepare the phenolic resin or the phenoliccrosslinker composition. The phenolic compound may be a monohydric,dihydric, or polyhydric phenol. Suitable monohydric, dihydric, orpolyhydric phenols include, but are not limited to, phenol;dihydricphenols such as resorcinol, catechol, hydroquinone;dihydroxybiphenol; alkylidenebisphenols, such as 4,4′-methylenediphenol(bisphenol F), and 4,4′-isopropylidenediphenol (bisphenol A);trihydroxybiphenol; and thiobisphenols. The benzene ring of themonohydric, dihydric, or polyhydric phenols can be substituted in theortho, meta, and/or para positions, by one or more linear, branched, orcyclic C₁-C₃₀ alkyl, or halogen (F, Cl, or Br). For example, the benzenering can be substituted by C₁-C₆ alkyl, or C₁-C₄ alkyl. Exemplaryphenolic compounds include phenol or resorcinol; or phenol or resorcinolsubstituted with one or more methyl groups, such as cresol, xylenol, ormethyl resorcinol.

The phenolic resin can be a monohydric, dihydric, or polyhydricphenol-aldehyde resin known to one skilled in the art. The monohydric,dihydric, or polyhydric phenol of the phenol-aldehyde resin isunsubstituted or substituted with one or more linear, branched, orcyclic C₁-C₃₀ alkyl, or halogen (F, Cl, or BR). Any aldehyde known inthe art suitable for phenol-aldehyde condensation reaction may be usedto form phenol-aldehyde resins. Exemplary aldehydes includeformaldehyde, methylformcel, butylformcel, acetaldehyde, propionaldehde,butyraldehyde, crotonaldehyde, valeraldehyde, caproaldehyde,heptaldehyde, benzaldehyde, as well as compounds that decompose toaldehyde such as paraformaldehyde, trioxane, furfural,hexamethylenetriamine, aldol, β-hydroxybutyraldelhyde, and acetals, andmixtures thereof. A typical aldehyde used is formaldehyde.

The phenolic resin can be prepared by methods known to one skilled inthe art. For example, the process for preparing novolak resins can befound in U.S. Pat. Nos. 8,030,418 and 8,470,930, which are herebyincorporated by reference in their entirety; the process for preparingbase-modified alklyphenol-aldehyde resins can be found in U.S. Pat. No.8,030,418, which is hereby incorporated by reference in its entirety.

The phenolic resins can be used in the form of viscous solutions or,when dehydrated, brittle resins with varying softening points capable ofliquefying upon heating. The phenolic resin solution can be an aqueoussolution, or the phenolic resin can be dissolved in an organic solventsuch as alcohols, ketones, esters, or aromatic solvents. Suitableorganic solvents include, but are not limited to, n-butanol, acetone,2-butoxy-ethanol-1, xylene, propylene glycol, N-butyl Cellosolve,diethylene glycol monoethyl ether, and other aromatic solvents or estersolvents, and mixtures thereof.

When employing the method to chemically bond a phenolic resin with anon-phenolic polymer, the non-phenolic polymer modified by the phenolicfatty acid compound can be reacted with the phenolic resin after thephenolic resin is formed.

Alternatively, the non-phenolic polymer modified by the phenolic fattyacid compound can be reacted with a phenolic crosslinker compositionbefore or during the components in the phenolic crosslinker compositionreact to form the phenolic resin. The phenolic crosslinker compositionmay comprise a phenolic compound, and/or aldehyde, and any componentthat can assist in forming a phenolic resin.

Coating Composition

In some embodiments, a coating composition is prepared by reacting aphenolic fatty acid compound, such as a phenol stearic acid compound, adiacid and a diol to produce a hydroxyl phenyl functional polymer, andblending the hydroxyl phenyl functional polymer with a phenoliccrosslinker in the presence of a non-aqueous solvent to form the coatingcomposition, wherein the acid number of the hydroxyl phenyl functionalpolymer is less than about 30 mg KOH/resin.

A monomer component may react with the phenol fatty acid compound toproduce a hydroxyl phenyl functional polymer. The polymer may be apolyester, an acrylic compound, a polyamide, an epoxy resin, and thelike, or a combination thereof. For example, the polymer may be apolyester prepared from a diol and a diacid, such that hydroxyl, amine,or glycidyl groups are available to react with the carboxylic acid ofthe phenol fatty acid compound.

The phenolic fatty acid compound operates in the coating composition asdescribed above.

Suitable ethylenically unsaturated monomer components for preparing thehydroxyl phenyl functional polymer, and the initiator used to polymerizethe ethylenically unsaturated monomers have been discussed herein.

Epoxidized vegetable oils can be used as the epoxy resin used to formthe hydroxyl phenyl functional polymer. Epoxidized vegetable oils can beprepared from vegetable oils by, for example, adding hydrogen peroxideand formic or acetic acid to the vegetable oil, and then holding themixture at an elevated temperature until some or all of thecarbon-carbon double bonds are converted to epoxide groups.

Vegetable oils contain primarily glycerides which are triesters ofglycerol and fatty acids with varying degrees of unsaturation. Forexample, suitable epoxidized vegetable oils can be made from vegetableoils (fatty acid triglycerides) such as esters of glycerol and fattyacids having an alkyl chain of about 12 to about 24 carbon atoms. Fattyacid glycerides which are triglycerides in unsaturated glyceride oilsare generally referred to as drying oils or semidrying oils. Drying oilsinclude, for non-limiting example, linseed oil, perilla oil andcombinations thereof, while semidrying oils include, without limitation,tall oil, soy bean oil, safflower oil and combinations thereof.Triglyceride oils in some embodiments have identical fatty acid chainsor alternatively have different fatty acid chains attached to the sameglycerol molecule. In some embodiments, the oils have fatty acid chainscontaining non-conjugated double bonds. In some embodiments, singledouble bond or conjugated double bond fatty acid chains are used inminor amounts. Double bond unsaturation in glycerides can be measured byiodine value (number) which indicates the degree of double bondunsaturation in the fatty acid chains. Unsaturated fatty acid glycerideoils employed in some embodiments of the invention have an iodine valuegreater than about 25 and alternatively between about 100 and about 210.

Naturally occurring vegetable oils for use in the invention can be fornon-limiting example, mixtures of fatty acid chains present asglycerides, and include without limitation a distribution of fatty acidesters of glyceride, where the fatty acid distribution may be random butwithin an established range that may vary moderately depending on thegrowing conditions of the vegetable source. Soybean oil is employed insome embodiments which comprises approximately about 11% palmitic, about4% stearic, about 25% oleic, about 51% linolenic, and about 9% linoleicfatty acids, where oleic, linoleic and linolenic are unsaturated fattyacids. Unsaturated vegetable oils employed include without limitation,glyceride oils containing non-conjugated unsaturated fatty acidglyceride esters such as linoleic and linolenic fatty acids.

Unsaturated glyceride oils include, without limitation, corn oil,cottonseed oil, rapeseed oil, hempseed oil, linseed oil, wild mustardoil, peanut oil, perilla oil, poppyseed oil, rapeseed oil, saffloweroil, sesame oil, soy bean oil, sunflower oil, canola oil, tall oil, andmixtures thereof. Suitable fatty acid glycerides include, fornon-limiting example, those which contain linoleic and linolenic fattyacid chains, oils such as hempseed oil, linseed oil, perilla oil,poppyseed oil, safflower oil, soy bean oil, sunflower oil, canola oil,tall oil, grapeseed oil, rattonseed oil, corn oil, and similar oilswhich contain high levels of linoleic and linolenic fatty acidglyceride. Glycerides can contain lesser amounts of saturated fattyacids in some embodiments. For example, soy bean oil can be employedwhich contains predominantly linoleic and linolenic fatty acidglycerides. Combinations of such oils are employed in some embodiments.Vegetable oils can by fully or partially epoxidized by known processes,for example, using acids such as peroxy acid for epoxidation ofunsaturated double bonds of the unsaturated vegetable oil. Unsaturatedglyceride oils employed in some embodiments include mono-, di-glyceridesand mixtures thereof with tri-glycerides or fatty acid esters ofsaturated and unsaturated fatty acids.

In some embodiments, the epoxidized vegetable oil comprises corn oil,cottonseed oil, grapeseed oil, hempseed oil, linseed oil, wild mustardoil, peanut oil, perilla oil, poppyseed oil, rapeseed oil, saffloweroil, sesame oil, soy bean oil, sunflower oil, canola oil, tall oil, afatty acid ester, monoglyceride or diglyceride of such oils, or amixture thereof.

Commercially available sources of epoxidized vegetable oils are used insome embodiments, for example, epoxidized soy oil sold under the tradedesignations “VIKOLOX” and “VIKOFLEX 7170” (Arkema, Inc), “DRAPEX 6.8”(Chemtura Corporation), and “PLAS-CHECK 775” (Ferro Corp.) Othersuitable epoxidized vegetable oils include, for on-limiting example,epoxidized linseed oil sold under the trade designations “VIKOFLEX 7190”(Arkema, Inc.) and “DRAPEX 10.4” (Chemtura Corporation), epoxidizedcotton seed oil, epoxidized carthamus oil and mixtures thereof.Epoxidized soy bean oil is employed in some embodiments.

In some embodiments, the hydroxyl functional material used to form thehydroxyl functional polymer by reaction with the epoxidized vegetableoil includes, without limitation, propylene glycol, ethylene glycol,1,3-propane diol, neopentyl glycol, trimethylol propane, diethyleneglycol, a polyether glycol, a polyester, a polycarbonate, a polyolefin,a hydroxyl functional polyolefin, and combinations thereof. The hydroxylfunctional material includes an alcohol in some embodiments such asn-butanol, 2-ethyl hexanol, benzyl alcohol, or combination thereof withdiols or polyols.

Suitable reactions and monomers for preparing polyamides and theresulting hydroxyl phenyl functional polymer have been discussed herein.

The acid number of the hydroxyl phenyl functional polymer is less thanabout 30 mg KOH/resin ion certain embodiments of the invention. Thisacid number can improve pigment dispersion, substrate wetting, adhesionand corrosion resistance of the coating composition.

Suitable catalysts for reacting the carboxylic acid group of thephenolic fatty acid compound with a carboxylic acid-reactive functionalgroup to introduce a hydroxyl phenyl functional into the non-phenolicpolymer has been described herein.

In some embodiments, the compounds used to form the hydroxyl phenylfunctional polymer are heated in the presence of a catalyst and asolvent (such as propylene glycol) to a temperature of about 50 to about160° C. Optionally, another solvent (such as ethylene glycol monobutylether or diethylene glycol monoethyl ether) can be included in thesynthesis of the epoxidized vegetable oil and hydroxyl functionalmaterial to help control viscosity. Suitable solvents include fornon-limiting example, a ketone such as methyl amyl ketone, an aromaticsolvent such as xylene or Aromatic 100, an ester solvent or othernon-hydroxyl functional solvent, and mixtures thereof. Up to about 90%of a solvent based on the total weight reaction mixture is employed invarious embodiments, or about 5 to about 30% is employed. Solventsselected from those described above as well as other solvents including,without limitation, hydroxyl functional solvents can be added uponcooling. In some embodiments, it is desirable to have a final NV(non-volatile content by weight) of about 30 to about 50.

In some embodiments, the hydroxyl phenyl functional polymer ischemically reacted with a phenolic resin or a phenolic crosslinkercapable of forming the phenolic resin to form a curable coatingcomposition. Suitable phenolic resins or phenolic crosslinkercompositions have been discussed herein. The weight ratio of thephenolic resins or phenolic crosslinkers to the hydroxyl functionalphenyl polyester may be from about 10/90 to about 40/60 at about 30-60%solids. The resulting coating composition may provide excellent filmperformance at very short baking for coil applications.

Optionally, the reaction of the hydroxyl phenyl functional polymer andthe phenolic resin or the phenolic crosslinker can occur in the presenceof a cure catalyst. Suitable cure catalysts include, for non-limitingexample, dodecyl benzene sulfonic acid, p-toluene sulfonic acid,phosphoric acid, and mixtures thereof. In some embodiments, otherpolymers may be blended into the coating composition, such aspolyethers, polyesters, polycarbonates, polyurethanes, and mixturesthereof. Cure conditions for packaging coatings in some embodiments areabout 5 to about 60 seconds at about 400° F. to about 600° F., andalternatively about 5 seconds to about 20 seconds at about 400° F. toabout 500° F.

The copolymers and the coating compositions can include conventionaladditives known to those skilled in the art, such as flow agents,surface active agents, defoamers, anti-cratering additives, lubricants,meat-release additives, and cure catalysts.

In some embodiments, one or more coating compositions are applied to asubstrate, such as cans, metal cans, easy-open-ends, packaging,containers, receptacles, can ends, or any portions thereof used to holdor touch any type of food or beverage. In some embodiments, one or morecoatings are applied in addition to the coating compositions. Forexample, a prime coat may be applied between the substrate and thecoating composition.

The coating compositions can be applied to substrates in any mannerknown to those skilled in the art. In some embodiments, the coatingcompositions are sprayed or roll coated onto a substrate.

When applied, the coating compositions contain, for non-limitingexample, between about 20 wt % and about 40 wt % of polymeric solidsrelative to about 60 wt % to about 80 wt % of solvent. For someapplications, typically those other than spraying, solvent bornepolymeric solutions can contain, for example, between about 20 wt % andabout 60 wt % of polymer solids. Organic solvents are utilized in someembodiments to facilitate roll coating or other application methods andsuch solvents can include, without limitation, n-butanol,2-butoxy-ethanol-1, xylene, propylene glycol, N-butyl cellosolve,diethylene glycol monoethyl ether and other aromatic solvents and estersolvents, and mixtures thereof. In some embodiments, N-butyl cellosolveis used in combination with propylene glycol. The resulting coatingcompositions can applied by conventional methods known in the coatingindustry, for example, spraying, rolling, dipping, coil coating, andflow coating application methods. In some embodiments, after applicationonto a substrate, the coating composition is thermally cured attemperatures in the range of about 200° C. to about 250° C., or higher,for a time sufficient to effectuate complete curing as well asvolatilizing any fugitive components.

The coating compositions can be pigmented and/or opacified with knownpigments and opacifiers in some embodiments. For many uses, including,for instance, food use, the pigment can be zinc oxide, carbon black, ortitanium dioxide. The resulting coating compositions can be applied byconventional methods known in the coating industry, for example,spraying, rolling, dipping, and flow coating application methods, forboth clear and pigmented films. In some embodiments, after applicationonto a substrate, the coating composition is thermally cured attemperatures in the range of about 130° C. to about 250° C., or higher,for a time sufficient to effectuate complete curing as well asvolatilizing any fugitive components.

For substrates intended as beverage containers, the coating can beapplied at a rate in the range from about 0.5 msi to about 15 milligramsper square inch of polymer coating per square inch of exposed substratesurface. In some embodiments, the water-dispersible coating is appliedat a thickness between about 0.1 msi and about 1.15 msi.

For substrates intended as beverage easy-open-ends, the coating can beapplied at a rate in the range from about 1.5 to about 15 milligrams persquare inch of polymer coating per square inch of exposed substratesurface. Conventional packaging coating compositions are applied tometal at about 232 to about 247° C. When used as a coating for theeasy-open-end of a metal container, the coatings of the inventionexhibit resistance to retorted beverages, acidified coffees, andisotonic drinks. In some embodiments, the solids content of the coatingcomposition is greater than about 30% and the coating composition has aviscosity from about 35 to about 200 centipoise at 30% solids or aboveto produce a film weight of about 6 to about 8 msi (milligrams persquare inch) so that over blister is minimized and so that the film canhave good chemical resistance, such as aluminum pick-up resistance. Someof the coating compositions of can be used for both inside and outsideeasy-open-end applications.

Process of Bonding a Phenolic Resin with a Synthetic Fabric Material

Another aspect of the invention relates to a method for chemicallybonding a phenolic resin with a synthetic fabric material. The methodcomprises contacting a phenolic fatty acid compound with a syntheticfabric material to introduce a hydroxy phenyl functional group into thesynthetic fabric material. The method further comprises reacting thehydroxy phenyl functional group contained in the synthetic fabricmaterial with a phenolic resin or a phenolic crosslinker compositioncapable of forming a phenolic resin, to chemically bond the phenolicresin with the synthetic fabric material.

The synthetic fabric material does not react, or only reacts minimally,with the phenolic resin, without the presence of the phenolic fatty acidcompound. As discussed in the embodiments above, the method takesadvantage of the bi-functionality of the phenolic fatty acid compound,i.e., the carboxylic acid functionality and the hydroxy phenylfunctionality, to chemically bond the synthetic fabric and the phenolicresin phase: the carboxylic acid group of the phenolic fatty acidcompound can react with a carboxylic acid-reactive functional groupwithin the synthetic fabric material to introduce the hydroxy phenylfunctionality from the phenolic fatty acid compound into the syntheticfabric material; while the hydroxy phenyl functionality of the phenolicfatty acid compound (i.e., the functional group that is being introducedinto the synthetic fabric material) can chemically react withhydroxymethyl or other methylene donor in the phenolic resin.

The step of contacting the phenolic fatty acid compound with thesynthetic fabric material to introduce a hydroxy phenyl functional groupinto the synthetic fabric material can be carried out by liquefying(e.g., melting) the synthetic fabric material into a molten state; andmixing the molten synthetic fabric material with the phenolic fatty acidcompound. This step can also be carried out by dissolving the syntheticfabric material in a solution of the phenolic fatty acid compound (as anaqueous solution or a solution containing an organic solvent), and/orheating.

The hydroxy phenyl functional group can be introduced into the syntheticfabric material by chemically reacting the carboxylic acid group of thephenolic fatty acid compound with a carboxylic acid-reactive functionalgroup of the synthetic fabric material in the presence of suitablecatalysts. The chemical reaction mechanism and suitable catalysts usedfor introducing the hydroxy phenyl functionality into the syntheticfabric material are the same as the reaction mechanism and suitablecatalysts for introducing the hydroxy phenyl functionality into thenon-phenolic polymer, as discussed in the above embodiments.

Alternatively, the hydroxy phenyl functional group can be introducedinto the synthetic fabric material by physically dispersing the phenolicfatty acid compound in the synthetic fabric material. When the moltensynthetic fabric materials are mixed with the phenolic fatty acidcompound and the mixture are re-solidified, the phenolic fatty acidcompound can still be immobilized in the re-solidified synthetic fabricmaterials through molecular interactions between the phenolic fatty acidcompound and the synthetic fabric material phase, such as hydrogenbonding, electrostatic interaction, and/or Van der Waals interactions.Moreover, when the mixture of molten synthetic fabric materials and thephenolic fatty acid compound are re-solidified, certain phenolic fattyacid molecules likely emerge on the surface of the synthetic fabricmaterial through hydrophobic interaction and surface tension, therebyimmobilizing some hydroxy phenyl functional groups (from the phenolicfatty acid molecules) on the surface of the synthetic fabric materials.

The resulting synthetic fabric materials, modified by the phenolic fattyacid compound, thus contain hydroxy phenyl functional groups to reactwith the phenolic resin. The modified synthetic fabric material can bere-solidified into a fabric, depending on the shape or form of thedesirable fabric, by methods known to one skilled in the art of makingsynthetic fabric.

The reaction mechanism and suitable catalysts used for reacting thehydroxy phenyl functionality, introduced into the synthetic fabricmaterial, with the phenolic resin are the same as the reaction mechanismand suitable catalysts for reacting the hydroxy phenyl functionality,introduced into the non-phenolic polymer, with the phenolic resin, asdiscussed in the above embodiments.

The phenolic fatty acid compounds suitable for utilization in the methodare the same as suitable phenolic fatty acid compounds for chemicallybonding a phenolic resin with a non-phenolic polymer, as discussed inthe above embodiments. Exemplary phenolic fatty acid compounds includehydroxyphenyl stearic acid (e.g., [9,10]-(p-hydroxyphenyl)-octadecanoicacid), hydroxyphenyl oleic acid, hydroxyphenyl linoleic acid,hydroxyphenyl palmitic acid, hydroxyphenyl behenic acid, andcombinations thereof. The phenolic fatty acid compound can be used in anamount ranging from about 0.1 wt % to about 20 wt %, for instance, fromabout 0.5 wt % to about 10 wt %, from about 1 wt % to about 15 wt %,from about 2 wt % to about 10 wt %, from 1 wt % to about 5 wt %, or fromabout 1 wt % to about 3 wt % of the synthetic fabric material. In oneembodiment, the phenolic fatty acid compound is hydroxyphenyl stearicacid, and is used in an amount ranging from about 0.1 wt % to about 20wt %, for instance, from about 1 wt % to about 15 wt %, or from about 2wt % to about 10 wt % of the synthetic fabric material.

Any synthetic polymers that can be used as a reinforced material can beused as the synthetic fabric material in the method. Suitable syntheticfabric materials include any polyester, polyether, polyacetate, acryliccompound, polyamide, polyamine, polysulfone, for instance, those thathave been discussed as non-phenolic polymers in the above embodiments,and combinations thereof. Typical synthetic fabric materials usedinclude nylon, rayon, polyester, aramid, or polysulfone, as discussedand exemplified in the above embodiments. These synthetic fabricmaterials may be in the form of, for instance, filaments, fibers, cords,or fabric sheets.

Suitable phenolic resins or phenolic crosslinker compositions forutilization in the method are the same as those phenolic resins orphenolic crosslinker compositions used in the reaction between thenon-phenolic polymer and phenolic resin, as discussed in the aboveembodiments.

The phenolic resins can be used in the form of aqueous, viscoussolutions or, when dehydrated, brittle resins with varying softeningpoints and capable of liquefying upon heating. The phenolic resinsolution can be an aqueous solution, or the phenolic resin can bedissolved in an organic solvent such as an alcohol, ketone, ester, oraromatic solvent. Suitable organic solvents include, but are not limitedto, n-butanol, acetone, 2-butoxy-ethanol-1, xylene, propylene glycol,N-butyl Cellosolve, diethylene glycol monoethyl ether, and otheraromatic solvents or ester solvents, and mixtures thereof.

The phenolic resin may further comprise an elastomeric latex. Forexample, the phenolic resin can be a widely used adhesive—resorcinolformaldehyde latex (RFL). Any latex known to make RFL adhesive can beused. For example, the latex component can be a mixture of SBR (styrenebutadiene rubber) and VP (vinyl pyridine) latex (i.e.,styrene-butadiene-2-vinyl pyridine latex). The aqueous solutions of RFLcan differ in their solids content, pH and viscosity; and selection ofthese parameters depend on type of fabric and the polymer matrix of thearticle to be reinforced.

In preparing RFL, the phenolic resin may be pre-formed condensationproduct between a phenolic compound and one or more aldehydes; and theresorcinol-formaldehyde resin can be mixed with a suitable polymericlatex to form a RFL. Alternatively, a suitable polymeric latex can bepre-mixed with a phenolic crosslinker composition, e.g., a reactionsystem of resorcinol and formaldehyde, before or during reactingresorcinol with formaldehyde to form resorcinol-formaldehyde resin.

The reaction of the phenolic fatty acid compound-modified syntheticfabric material with the phenolic resin or phenolic crosslinkercomposition can be performed by various techniques known in the area offorming reinforced material. For example, the phenolic fatty acidcompound-modified synthetic fabric material can be soaked or dipped inan aqueous solution of the phenolic resin or the phenolic crosslinkercomposition, thereby facilitating the chemical bonding of the phenolicresin with the synthetic fabric material.

One exemplary reaction system is modified-RFL dipping technology, wherethe phenolic fatty acid compound-modified synthetic fabric materials(e.g., various reinforcing fabric sheets, fibers, or cords) are soakedor dipped in the RFL solution.

The process for applying RFL onto the modified synthetic fabricmaterials is the same as conventional RFL dipping technology. Theprocess basically involves soaking or dipping the modified syntheticfabric materials in a RFL solution, followed by removal of the excessRFL solution on the surface of the modified synthetic fabric materials.When the modified synthetic fabric materials is soaked or dipped in theRFL solution, the modified synthetic fabric materials chemically bondwith the RFL through the reaction between the hydroxyphenol functionalgroup contained in the modified synthetic fabric materials with the RFL.This reaction can be carried out in the presence of a basic catalyst inthe RFL solution. Suitable basic catalysts include, but are not limitedto, ammonium hydroxide, tertiary amines, alkali and alkaline earth metaloxides and hydroxides, and combinations thereof.

Typically, the synthetic fabric material does not react, or reacts onlyminimally, with the phenolic resin, such as RFL, without the presence ofthe phenolic fatty acid compound. For instance, polyester yarns, aramidyarns, or fabrics do not contain many reactive functional groups andtherefore do not give satisfactory adhesion results to articles to bereinforced (e.g., rubber compound) when treated with conventional RFLdipping technology. The phenolic fatty acid compound-modified syntheticfabric materials, however, contain the hydroxy phenyl functionality thatcan chemically react with RFL to provide an enhanced bonding andenhanced adhesion between the modified synthetic fabric materials andthe RFL.

The RFL-modified synthetic fabric materials can then be treated bydrying and/or heating, e.g., using ovens. The resulting reinforcedmaterial can be incorporated into an article to be reinforced (e.g., arubber compound). The adhesion between the reinforced material and thearticle can be physical interactions or chemical interactions, such aschroman ring and methylene bridge formation. Cured RFL contains acontinuous resin phase with particles of latex dispersed throughout thisphase. The latex also provides reactive sites which can form covalentbonds to the article (e.g., rubber compound) via conventional sulfurcrosslinking.

Another exemplary reaction system is modified-dry bonding adhesiontechnology, where the phenolic fatty acid compound-modified syntheticfabric materials (e.g., various reinforcing fabric sheets, fibers, orcords) are added to the article that is desired to be reinforced (e.g.,a rubber compound). A phenolic crosslinker composition, such asresorcinol or resorcinol-formaldehyde solid resin, is also added to thearticle, along with a suitable methylene donor. Any suitable methylenedonor can be used, including but not limited to, hexamethylenetetramine(HMTA), di-, tri-, tetra-, penta-, or hexa-N-methylol-melamine or theirpartially or completely etherified or esterified derivatives, forexample hexamethoxymethylmelamine (HMMM), or nitromethylpropanol (NMP);oxaolidine or N-methyl-1,3,5-dioxazine. Upon curing the rubber compound,the methylene donor in the rubber compound crosslinks with the phenoliccompound or phenolic resin; the phenolic resin reacts with thehydroxyphenol group of the embedded phenolic fatty acidcompound-modified reinforcing materials, thereby promoting the adhesionof the rubber to the modified reinforcing materials. Advantageously,this embodiment of the invention avoids the use of RFL, or similarmaterial, altogether.

Reinforcing Applications

In some embodiments, the non-phenolic polymers (such as the syntheticfabric materials) are chemically bonded with the phenolic resin to beused as a reinforced material. The method of the invention furthercomprises combining the phenolic resin on or in an article to bereinforced, prior to or after the reacting step to chemically bond thephenolic resin with the non-phenolic polymer (e.g., the synthetic fabricmaterials). The article to be reinforced can be, for instance, a circuitboard substrate, a fiberglass, or a rubber composition.

The method employs the phenolic fatty acid compound to modify thereinforcing material, i.e., the non-phenolic polymers, to introduce ahydroxy phenol function group into the reinforcing material, renderingit reactive to the phenolic resin.

The phenolic resin can react with the non-phenolic polymer first, e.g.,by contacting the non-phenolic polymer (modified with the phenolic fattyacid) with the phenolic resin, as exemplified above via modified-RFLtechnology; and then the non-phenolic polymer bonded with the phenolicresin can be combined with (or incorporated into) the article to bereinforced (e.g., circuit board substrate, a fiberglass, or a rubbercomposition).

Alternatively, the phenolic resin can be combined with (or incorporatedinto) the article to be reinforced (e.g., circuit board substrate, afiberglass, or a rubber composition) before or during the non-phenolicpolymer (modified with the phenolic fatty acid) is incorporated into thearticle; then the phenolic resin that is combined with the article canreact with the non-phenolic polymer (modified with the phenolic fattyacid) after or during the phenolic resin reacts or interacts with thearticle, as exemplified above via modified-dry bonding adhesiontechnology.

By this method, the adhesion between the reinforcing material, i.e., thephenolic fatty acid-modified non-phenolic polymer, and the article to bereinforced can be significantly enhanced (by chemical bonding betweenthe reinforcing material and the phenolic resin, as well as the chemicalbonding/strong physical interaction between the phenolic resin and thearticle).

Fabric-Reinforced Articles

Accordingly, one aspect of the invention relates to a synthetic-fabricreinforced rubber composition. The composition comprises a rubbercomposition and a synthetic fabric phase. The synthetic fabric phase hasbeen (a) modified by a phenolic fatty acid compound to contain a hydroxyphenyl functional group, and (b) coated with a phenolic resin, whereinthe synthetic fabric phase and the coated phenolic resin are chemicallybonded through the hydroxy phenyl functional group. The synthetic fabricphase can be used as a reinforced material for the rubber composition.

The rubber composition comprises, besides the reinforced materials, oneor more rubber compounds. The rubber compound includes a natural rubber,a synthetic rubber, or a mixture thereof. For instance, the rubbercomposition is a natural rubber composition.

Alternatively, the rubber composition can be a synthetic rubbercomposition. Representative synthetic rubbery polymers includediene-based synthetic rubbers, such as homopolymers of conjugated dienemonomers, and copolymers and terpolymers of the conjugated dienemonomers with monovinyl aromatic monomers and trienes. Exemplarydiene-based compounds include, but are not limited to, polyisoprene suchas 1,4-cis-polyisoprene and 3,4-polyisoprene; neoprene; polystyrene;polybutadiene; 1,2-vinyl-polybutadiene; butadiene-isoprene copolymer;butadiene-isoprene-styrene terpolymer; isoprene-styrene copolymer;styrene/isoprene/butadiene copolymers; styrene/isoprene copolymers;emulsion styrene-butadiene copolymer; solution styrene/butadienecopolymers; butyl rubber such as isobutylene rubber; ethylene/propylenecopolymers such as ethylene propylene diene monomer (EPDM); and blendsthereof. A rubber component, having a branched structure formed by useof a polyfunctional modifier such as tin tetrachloride, or amultifunctional monomer such as divinyl benzene, may also be used.Additional suitable rubber compounds include nitrile rubber,acrylonitrile-butadiene rubber (NBR), silicone rubber, thefluoroelastomers, ethylene acrylic rubber, ethylene vinyl acetatecopolymer (EVA), epichlorohydrin rubbers, chlorinated polyethylenerubbers such as chloroprene rubbers, chlorosulfonated polyethylenerubbers, hydrogenated nitrile rubber, hydrogenated isoprene-isobutylenerubbers, tetrafluoroethylene-propylene rubbers, and blends thereof.

The rubber composition can also be a blend of natural rubber with asynthetic rubber, a blend of different synthetic rubbers, or a blend ofnatural rubber with different synthetic rubbers. For instance, therubber composition can be a natural rubber/polybutadiene rubber blend, astyrene butadiene rubber-based blend, such as a styrene butadienerubber/natural rubber blend, or a styrene butadiene rubber/butadienerubber blend. When using a blend of rubber compounds, the blend ratiobetween different natural or synthetic rubbers can be flexible,depending on the properties desired for the rubber blend composition.

Also, the rubber composition may comprise additional materials, such asa methylene donor, one or more additives, one or more other reinforcingmaterials, and one or more oils. As known to the skilled in the art,these additional materials are selected and commonly used inconventional amounts.

Suitable methylene donors include, for instance, hexamethylenetetramine(HMTA), di-, tri-, tetra-, penta-, or hexa-N-methylol-melamine or theirpartially or completely etherified or esterified derivatives, forexample hexamethoxymethylmelamine (HMMM), oxazolidine orN-methyl-1,3,5-dioxazine, and mixtures thereof.

Suitable additives include, for instance, sulfur, carbon black, zincoxides, silica, waxes, antioxidant, antiozonants, peptizing agents,fatty acids, stearates, accelerators, curing agents, activators,retarders, a cobalt, adhesion promoters, resins such as tackifyingresins, plasticizers, pigments, additional fillers, and mixturesthereof.

Suitable other reinforcing materials include, for instance, glass, steel(brass, zinc or bronze plated), or other organic and inorganiccompositions. These reinforcing materials may be in the form of, forinstance, filaments, fibers, cords or fabrics.

Suitable oils include, for instance, mineral oils and naturally derivedoils. Examples of naturally derived oils include tall oil, linseed oil,and/or twig oil. Commercial examples of tall oil include, e.g., SYLFAT®FA-1 (Arizona Chemicals) and PAMAK 4® (Hercules Inc.). The one or moreoils may be contained in the rubber composition, relative to the totalweight of rubber compounds in the composition, less than about 5 wt %,for instance, less than about 2 wt %, less than about 1 wt %, less thanabout 0.6 wt %, less than about 0.4 wt %, less than about 0.3 wt %, orless than about 0.2 wt %. The presence of an oil in the rubbercomposition may aid in providing improved flexibility of the rubbercomposition after vulcanization.

The rubber compositions can be vulcanized by using mixing equipment andprocedures conventionally employed in the art. Likewise, the finalrubber products can be fabricated by using standard rubber curingtechniques. The reinforced rubber compounds can be cured in aconventional manner with known vulcanizing agents at about 0.1 to 10phr. A general disclosure of suitable vulcanizing agents may be found inKirk-Othmer, Encyclopedia of Chemical Technology (3rd ed., Wiley, NewYork, 1982) vol. 20, pp. 365 to 468 (particularly “Vulcanization Agentsand Auxiliary Materials,” pp. 390 to 402), and Vulcanization by A. Y.Coran, Encyclopedia of Polymer Science and Engineering (2nd ed., JohnWiley & Sons, Inc. 1989), both of which are incorporated herein byreference. Vulcanizing agents can be used alone or in combination.

When forming a synthetic fabric-reinforced rubber composition, twosheets of the rubber composition, for instance a top sheet and a bottomsheet, can be pressed onto the fabric through techniques known in theart, such as in a calendaring operation, and then cured.

The synthetic fabric-reinforced rubber composition employing thesynthetic fabric phase, which is chemically bonded with the coatedphenolic resin, exhibits significantly enhanced adhesion between thereinforcing synthetic fabric phase and the rubber compound, and thus canbe useful to make a wide variety of products, for instance, tires ortire components such as sidewall, tread (or treadstock, subtread),carcass ply, body ply skim, wirecoat, beadfiller, or overlay compoundsfor tires. Suitable products also include hoses, power belts, conveyorbelts, printing rolls, rubber shoe heels, rubber shoe soles, rubberwringers, automobile floor mats, mud flaps for trucks, ball mill liners,and weather strips.

Another aspect of the invention relates to a synthetic-fabric reinforcedarticle. The synthetic-fabric reinforced article comprises an articlecontaining a phenolic resin, and a synthetic fabric phase. The syntheticfabric phase is modified by a phenolic fatty acid compound to contain ahydroxy phenyl functional group. The synthetic fabric phase and thearticle are chemically bonded through the hydroxy phenyl functionalgroup. The article can be, for instance, a rubber composition, a circuitboard substrate, or a fiberglass.

The articles to be reinforced may have contained phenolic resin to bondthe hydroxy phenyl functional group that has been introduced into thesynthetic fabric phase. The synthetic fabric phase thus may not need tobe combined with a phenolic resin before being combined with thearticle. For example, a rubber composition can often contain somephenolic resin or phenolic crosslinking composition that is capable offorming a phenolic resin. Circuit board substrates are often producedfrom phenol formaldehyde resins or other polymeric materials containingphenolic resin. Accordingly, by using the phenolic fatty acid compoundto modify the synthetic fabric phase, the application of additionaladhesive onto the synthetic fabric phase may not be necessary, as longas the article to be reinforced contain some phenolic resin. Theresulting synthetic-fabric reinforced article can still have goodadhesion between the reinforcing fabric phase and the polymer matrixphase. Upon combining the phenolic fatty acid compound-modifiedsynthetic fabric phase with the article containing a phenolic resin, thehydroxy phenyl functional group in the synthetic fabric phase canchemically bond with the phenolic resin in the article, under conditionseffectively to allow such reaction to happen, e.g., under curingconditions, with suitable catalysts, as discussed in the aboveembodiments.

Any techniques known to one skilled in the art for molding thesynthetic-fabric reinforced article can be used. The synthetic-fabricphase preformed and modified by phenolic fatty acid (and/or phenolicresins) can be in a form of fiber, filament, cord, or fabric sheet,placed on or in a mold, or injected into a mold. The article (polymermatrix without reinforcement, e.g., a rubber compound, a circuit boardsubstrate material, or a fiberglass material) can be similarly placed onor in a mold, or injected into a mold. The mixture in the mold is thencured, leaving the synthetic-fabric reinforced article in the shapecreated by the mold. Heat and/or pressure are sometimes used to cure thearticle and improve the quality of the final article.

EXAMPLES

The following examples are given as particular embodiments of theinvention and to demonstrate the practice and advantages thereof. It isto be understood that the examples are given by way of illustration andare not intended to limit the specification or the claims that follow inany manner.

Example 1: Preparation of Phenol Stearic Acid

100 parts of phenol and 5 parts of p-toluenesulfonic acid (PTSA) wereheated in a glass flask equipped with a stirrer, thermometer, and watercooled condenser arranged to return condensed water to the flask. Thereaction mixture was heated to between 90 and 105° C. Over a period of 3hours, 100 parts of oleic acid were added to the reaction mixture whilemaintaining 90-105° C. reaction temperature. The reaction was allowed toproceed for 5 hours while checking for unreacted phenol by GC everyhour. At the end of 5 hours, 45 parts of 50% caustic solution was loadedslowly to the reaction mixture to neutralize the PTSA. The unreactedphenol was removed by distillation under 40 mm vacuum at a temperatureof 130° C. Optionally, to further reduce the residual phenol, 10 pphdistilled water was loaded to the reaction mixture and distilled at 130°C. and 40 mm vacuum. The resulting product, recovered in the amount of135 parts, showed by titration to an acid number of 113.

Although preferred embodiments have been depicted and described indetail herein, it will be apparent to those skilled in the art thatvarious modifications, additions, substitutions, and the like can bemade without departing from the spirit of the invention and these aretherefore considered to be within the scope of the invention as definedin the claims which follow.

1. A method for chemically bonding a phenolic resin with a non-phenolicpolymer, comprising: contacting a phenolic fatty acid compound with anon-phenolic polymer having a functional group reactive to an carboxylicacid group of a fatty acid, to react the carboxylic acid-reactivefunctional group of the non-phenolic polymer with the carboxylic acidgroup of the phenolic fatty acid compound, thereby attaching a hydroxyphenyl functional group to the non-phenolic polymer; and reacting thehydroxy phenyl functional group of the non-phenolic polymer with aphenolic resin or a phenolic crosslinker composition capable of forminga phenolic resin, to chemically bond the phenolic resin with thenon-phenolic polymer.
 2. The method of claim 1, wherein, without thepresence of the phenolic fatty acid compound, the non-phenolic polymerdoes not react, or reacts minimally, with the phenolic resin.
 3. Themethod of claim 1, wherein the contacting occurs in the presence of ametal-based catalyst selected from the group consisting ofantimony-based catalyst, tin-based catalyst, titanium-based catalyst,and co-catalyst of phosphorus and a metal element, and combinationsthereof; or an acidic catalyst selected from the group consisting of alewis acid, a sulfonic acid, a triflic acid, a triflate salt of a metalof Group IIA, IIB, IIIA, IIIB, or VIIIA, a mixture of triflate salts,and combinations thereof.
 4. The method of claim 1, wherein the reactionof the hydroxy phenyl functional group with the phenolic resin or thephenolic crosslinker occurs in the presence of an basic catalystselected from the group consisting of ammonium hydroxide, tertiaryamines, alkali and alkaline earth metal oxides and hydroxides, andcombinations thereof.
 5. The method of claim 1, wherein the non-phenolicpolymer is selected from the group consisting of a polyester, apolyether, a polyacetate, an acrylic compound, a polyamide, a polyamine,a polysulfone, and combinations thereof.
 6. The method of claim 1,wherein the phenolic resin is a monohydric, dihydric, or polyhydricphenol-aldehyde resin, wherein the monohydric, dihydric, or polyhydricphenol of the phenol-aldehyde resin is unsubstituted or substituted withone or more linear, branched, or cyclic C₁-C₃₀ alkyl groups.
 7. Themethod of claim 1, wherein the non-phenolic polymer is a syntheticfabric selected from the group consisting of nylon, rayon, polyester,aramid, polysulfone, and combinations thereof.
 8. The method of claim 1,wherein the phenolic resin is a solution in water or an organic solvent.9. The method of claim 1, wherein the non-phenolic polymer is an acryliccompound prepared from an ethylenically unsaturated monomer componentcomprising butyl acrylate, methyl methacrylate, hydroxy propylmethacrylate, hydroxy ethyl acrylate, glycidyl methacrylate, acrylicacid, methacrylic acid, acetoacetoxy ethyl methacrylate, a phosphateester monomethacrylate, or combinations thereof.
 10. The method of claim1, wherein the phenolic fatty acid compound is selected from the groupconsisting of comprises hydroxyphenyl stearic acid, hydroxyphenyl oleicacid, hydroxyphenyl linoleic acid, and combinations thereof.
 11. Themethod of claim 1, wherein the phenolic fatty acid compound comprises[9,10]-(p-hydroxyphenyl)-octadecanoic acid.
 12. The method of claim 1,wherein the phenolic fatty acid compound ranges about 0.1 wt % to about50 wt % of the non-phenolic polymer.